Elastic fluid turbine



April 23, 1946. .1. H. DORAN ELASTIC FLUID TURBINE Filed July 25, 1944 Fi gl.

. Inventor: John H. Devan,

His Attorney.

Patented Apr. 23, 1946 ELASTIC FLUID TURBINE John H. Doran, Scotia, 1C, assignor toGencral Electric Company, a corporation .of New York Application July .25, 1944, .Serial No. 546,558

3 Claims.

The present invention relates to elastic fluid turbines having a plurality of series-connected stages and means .for extracting liquid therefrom formed by condensation of some .of the elastic fluid in its passage through the turbine. Centrifugal action to which such liquid is .sub- ,jected forces it radiallyoutw-ard and accordingly it has been the practice heretofore to-remove liquid from radially outer regions of the fluid flow passages in the turbine.

The object of my invention is to provide an improved construction of elastic turbines whereby liquid or condensate may the 1efiectively removed .from the outer as well as the intermediate and inner portions of the flow passages. This is accomplished according to my invention by the provision of a plurality of concentrically spaced, preferably somewhat conical strips or rings attached to the inlet portion of a low pressure stage diaphragm for directing liquid impinging thereon into drain channels formed along the inlet edge portions of the diaphragm partitions. These can be made so as to interfere very little with the flow of steam.

For a better understanding of what I believe to be, novel and my invention, attention is .directed to the following description and the claims appended thereto in connection with the accompanying drawing.

In the accompanying drawing Fig. 1 illustrates a sectional view partly broken away of an elastic fluid turbine embodying my invention; Fig. 2 is an enlarged perspective view of a part of Fig. 1; and Fig. 3 illustrates a modification of my invention.

The elastic fluid turbine, Figs. 1 and 2, comprises an outer casing I with a plurality of axially spaced diaphragms 2, 3 attached thereto. A rotor 4 disposed within the casing has a shaft 5 and a plurality of bucket wheels 6 and 1 secured thereto. Each bucket wheel has a row of circumferentially spaced buckets 8 forming bucket passages between them. Each diaphragm is associated with one of the wheels and has a row of circumferentially spaced partitions 9 secured in known manner to an inner disk l0 and an outer band ll and forming nozzle passages between them for properly directing elastic fluid to the respective wheels 6 and I. On its passage through the turbine, elastic fluid discharged from wheel 6 which constitutes a higher pressure stage wheel is passed into the nozzle passages of the diaphragm 3 to be directed from the latter into the bucket passages of the bucket wheel 1 which latter constitutes a lower pressure stage.

The fluid discharged from the bucket wheel '8 contains a certain amount of liquid, water in the case of a steam turbine, which liquid upon impinging on the inlet edges of the succeeding partitions and buckets may cause considerable damage to the latter and also erosion of the surface thereof. Liquid discharged from the exit edges of the bucket blades has a direction of flow different from the direction of flow of the elastic fluid. The direction of flow of the liquid particles thrown from the buckets is partly radial and partly tangential and has a rather low velocity component in the direction of Steam flow. The different direction of flow of liquid and elastic .fluid and the different velocities thereof may cause substantial reduction of the efliciency of operation. Toremove some of this liquid, particularly from the outer regionsof the passages, the turbine casing I is provided with an annular channel .12 and a drain conduit l3 connected to the bottom portion thereof.

The arrangement so far described is well known in the art. According to my invention means are provided for extracting liquid, such as water, flowing through the radially inner and intermediate portions of the :fluid flow passages. This means in the present example comprises three concentrically spaced, preferably conically shaped rings l4, l5 and -16 supported on the thickened inlet edge portions of the partitions 9 of the low pressure stage diaphragm 3. Liquid entrained in the elastic fluid discharged from the :bucket wheel -'6 in the direction of the arrows indicated inFig. L2 impinges on the radially inner surfaces of the rings l4, l5, Hi. In order to collect the liquid and to limit its circumferential flowalong the rings M to IE each ring is provided with a plurality of circumferentially spaced scuppers or troughs I! each being fused or otherwise fastened along one edge of the ring. Liquid flowing into these troughs is passed into radial channels formed along the leading edges of the partitions. In the present example separate U-shaped channel members I8 are fused to the inlet edge portions of the partitions to form radial channels l9 therewith. Each trough l1 discharges through an opening 20 (Fig. 2) of the channel member 8 into the channel IS. The rings I4, 15, I6 and the troughs I! are fused to the channel members l9, which latter therefore act as a support for the rings and troughs on the partitions. The disk ill of the low pressure diaphragm 3 is provided with an annular groove or channel 2| having openings 22 establishing communication between the During operation, liquid impinging on the rings l4, 15, I6 is conducted into the different troughs or scuppers ll, whence the liquid flows into the radial partition channels I9. The liquid contained in the channels 19 of the upper diaphragm half flows radially inward through the openings 22 into the inner channel 2|. From this inner channel 2| the liquid flows through the partition channels l9 of the lower diaphragm half into the outer channel 23 to be discharged therefrom through the drain opening 25 into the casing channel l2. Liquidcollected' by the scuppers of the lower diaphragm half also flow into the radial channels is and within these channels flows radially outward directly into the outer annular channel 23 to be discharged therefrom through the opening 25 into the casing channel l2.

The modification of Fig. 3 comprises a partition with a disk 26 and a plurality of circumi'erentially spaced partitions 2'! secured at their inner ends to the disk 26. A channel member 28 corresponding to the channel members iii of Fig. 2 is secured to the inlet portion of each partition 2'! to form a radial channel 29 therewith. Liquid entrained in the elastic fluid is removed therefrom and conducted to the radial channels 29 by means of a circumferentially extending ring or cone 36 corresponding to the cones M to ii of Fig. 1 and a plurality of souppers or troughs 3i fused to the ring 30 and to the channel members 29. The scuppers in the present example are U-shaped in section and have a. radial length increasing in the direction towards the channel members 28. Each of the latter has a slot 32 for receiving liquid from one of the scuppers. One leg of each trough is fused to the inner surface of the ring 30 while the other leg is slightly spaced therefrom to admit liquid flow ing circumferentially along the ring 30 into the trough. The liquid conducted to the radial channels 29 is discharged therefrom through bores 33 in the disk into' an annular channel 34 corresponding to the channel 2| of Fig. 2. Except for the particular design of the troughs the arrangement of Fig. 3 is the same as that in Figs. 1 and 2.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. Elastic fluid turbine including a, plurality of stages each having a rotary bucket wheel and a stationary diaphragm with a plurality of circumierentially spaced partitions for conducting operating medium to the wheel, and means for extracting liquid entrained in the elastic fluid from a low pressure turbine stage comprising a circumferentially extending band secured to intermediate inlet edge portions of the partitions, separate troughs secured to the band adjacent the partitions and passages formed in the partitions and arranged to receive liquid directed thereto by said troughs.

2. Multi-stage elastic fluid turbine comprising a casing, a low pressure stage diaphragm supported in the casing and having a plurality of circumferentially spaced partitions, and means for extracting liquid entrained in the elastic fluid flowing through the turbine comprising a plurality of concentric rings secured to the inlet edge portions of the partitions at radially spaced locations thereon and channel means partly formed in the partitions and arranged to collect, receive and drain liquid impinging on the radially inner surface of said rings.

3. Multi-stage elastic fluid turbine comprising a casing, a plurality of diaphragms supported on the casing each having an inner disk, an outer band and a plurality of circumferentially spaced partitions secured at their ends to the disk and the band respectively, and means for extracting liquid entrained in the elastic fluid from a low pressure sta e of the turbine, said means comprising a plurality of 'concentric radia'lly spaced substantially conical rings secured to the inlet edge portions of the partitions of the diaphragm of said low pressure stage, a plurality of circumierentially spaced troughs each secured to a ring and to one of the partitionsand means for extracting liquid collected in the troughs, said means including radial channels formed in the partitions, ports in the inlet edges of the partitions communicating between the troughs and said radial channels, annular channels formed in the disk and the band and communicating with said radial channels, and a drain conduit connected to the bottom of the casing and communicating with the annular channels.

JOHN H. DORAN. 

